I am a painter in OZ and from what you say, you want to hide some garbagey old surface.
If a bit of roughness wont bother you, we have a product here called TEXTURE COTE. It is an acrylic, very thick, can be tinted most light colours and is applied with a texture roller. It is designed to hide the rough work of builders. (Painters make the worst builder look good) The roller sleeve has the appearance of a hull scrubber. Looks like fine wire but is a plastic material.(Like a brillo pad)
You should see texture cote around malls, shops etc.
Can give a small to very rough texture. Dries very hard and dont rub against it too hard.
Ask one of your local house painters. He should be able to put you on to what it is called where you are.
Love your attitude...Forget about the appearance...Go for simplicity..
Your DA man..